Mordant azo dyestuffs.



OTTO STAEHLIN, 0F HCHST-ON-THE-MAIN, GERIVZANY, ASSIGNOR T0 VORM.MEISTER LUCIUS & BRl'lNING, 0F HCDCHST-ON-THE-MAIN, GERMANY, A (303- IPORATION OF GERMANY.

MIORllihflihrll AZO DYESTUFFS.

No Drawing.

To all whom it may concern.

Be it known that I, OTTO STAEHLIN, Ph. 1)., chemist, a citizen of theEmpire of Germany, residing at H6chst-on-the-Main, Germany, haveinvented certain new and useful Improvements in New Mordant AzoDyestufl's,-of which the following is a specification. 5 F

My invention relates to the manufacture of new mordant dyestufis whichon addition of a potassium bichromate can be dyed in a single bath'dyeing wool green tints.

' The method of preparing said dyestufl's consists in combining thediazotized' picramic acid (Q-amino-t.6Tdinitrophen0l) with amonoalkyl-ether of the 1.8-di0xynaphthalene-4-sulfonic acid.

The new dyestufis have most probably the formula wherein R representsthe aryl radical of a monoalkyl ether of 1.8-dioXynaphthalene-4-'sulfonic acid- In other Words, they may probably be represented-by theformula:

an alkyl group such as CH C H or inversely. In the form of theirsodiumsalts,

. they are greenish-black powders soluble in water with aviolet-blue-color which on addition of a'mineral acid become cherry-red;they dissolve in concentrated sulfuric acid with a bluish-green colorand dye unmordanted wool, on addition of potassium bichromate and anacid, uniform Russian green tints of excellent fastness to milling andto light. V

The following example will serve to illus- Specification of LettersPatent.

Application filed October 1, 1913. Serial No. 792,790.

Patented 0st. 5,1915

trate my invention: 22.1 kilos of sodium pic-' ramate are diazotized inthe usual manner with 6.9 kilos of nitrite and 40 kilos of hydrochloric.acid. The diazo solution thus ob-' tamed is introduced, while wellstirring, at 1520 C.,into 'asolution of 30 kilos ofthe 4z-sulfonic acidafter having added to this solution 30 kilos ofsodium carbonate. Theunion occurs readilywithout decomposition. The sodium salt of thedyestufi' which most probably has the formula l 1&0; I 7 803x 0 icompletely separates within a few hours, whereupon it is filtered anddried. It forms a greenish-black powder, water with a violet-blue colorwhich becomes 7 cherry-red on addition of an acid; in concentratedsulfuric acid it dissolves with a bluish-green color.

. Having now described my invention, what I claim 1s:

1. As new articles of manufacture, the

. mordant dyestufis having most probably the formula OH I thalene, whichin the form of their sodiumv salts, are greenish-black powders, solublein water-with a violet-blue color turning cherry red on addition of amineral acid,

and dissolve in concentrated sulfuric acid' with a bluish-green color,dyeing Wool on addition of potassium bichromate and an acid uniformRussian-green tints fast to milling, and being remarkable for theirexcellent fastness to light.

readily soluble in I sodium salt of 1-ethoxy-S-oxynaphthalenfi 2. As anew article of manufacture, the *mordant dyestufi' having most probablythe formula l HO OCZH5 SOaNa.

N02 which is a greenish-black powder, soluble in water with aviolet-blue color turning cherry-red on addition of'a mineral acid,

milling and remarkable for their excellent fastness to light.

In testimony whereof I afiix my signature 20 in presence of twowitnesses.

DR. OTTO STAEHLIN.

Witnesses:

JEAN GRUND, CARL GRUND.

